Why is oceanic crust generally younger than continental crust?

Oceanic crust is generally much younger than continental crust because it is continuously recycled into Earth's mantle through the process of subduction.1

The primary reasons for this age disparity include:

• Continuous Formation and Destruction: New oceanic crust is constantly created at mid-ocean ridges through seafloor spreading. Because Earth's volume remains constant, this generation of new crust must be balanced by the destruction of older crust at subduction zones, where oceanic plates descend into the mantle and are recycled.21
• Density and Buoyancy: Oceanic crust is denser than continental crust. As it ages and cools, it becomes even denser, making it prone to subduction. In contrast, the lower density and greater buoyancy of continental crust prevent it from being easily subducted, allowing it to be preserved over billions of years.13

Consequently, while the oldest continental rocks date back more than 4 billion years, the oceanic crust is generally less than 200 million years old.41